Is this allowed?
Yes no doubt. Dogs are a creation of Allah and treating them, or any animal, with kindness that is due right upon them unless prevented otherwise.
The Prophet said =
أَنَّ رَجُلاً رَأَى كَلْبًا يَأْكُلُ الثَّرَى مِنَ الْعَطَشِ، فَأَخَذَ
الرَّجُلُ خُفَّهُ فَجَعَلَ يَغْرِفُ لَهُ بِهِ حَتَّى أَرْوَاهُ،
فَشَكَرَ اللَّهُ لَهُ فَأَدْخَلَهُ الْجَنَّةَ
"A man saw a dog eating
mud from thirst. The man took a shoe with water and kept on pouring
for the dog till it quenched its thirst. So Allah approved of his deed
and made him to enter Paradise."
بَيْنَمَا كَلْبٌ يُطِيفُ بِرَكِيَّةٍ كَادَ يَقْتُلُهُ الْعَطَشُ، إِذْ
رَأَتْهُ بَغِيٌّ مِنْ بَغَايَا بَنِي إِسْرَائِيلَ، فَنَزَعَتْ مُوقَهَا
فَسَقَتْهُ، فَغُفِرَ لَهَا بِهِ
"While a dog was going round a well and was about to die of thirst, an
Bani Israeli prostitute saw it and took off her shoe and watered it. So
Allah forgave her because of that good deed."
There's a gross culturally influenced misconception that somehow dogs are evil or dirty animals. However, this has absolutely no Quranic/hadith backing whatsoever.
So as a vet, you do your best to improve the lives of animals, including dogs InshaAllah